Add S3 upload with key templating and custom endpoint

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/upload/upload.go

@@ -0,0 +1,70 @@
+package upload
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	awsconfig "github.com/aws/aws-sdk-go-v2/config"
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+)
+
+// PutObjectAPI is the subset of *s3.Client used here. Tests inject a fake.
+type PutObjectAPI interface {
+	PutObject(ctx context.Context, in *s3.PutObjectInput, opts ...func(*s3.Options)) (*s3.PutObjectOutput, error)
+}
+
+// Opts configures a single upload.
+type Opts struct {
+	Bucket   string
+	Key      string
+	FilePath string
+}
+
+// RenderKey substitutes {version} and {filename} placeholders.
+func RenderKey(template, version, filename string) string {
+	r := strings.NewReplacer("{version}", version, "{filename}", filename)
+	return r.Replace(template)
+}
+
+// Upload PUTs FilePath at s3://Bucket/Key and returns the s3:// URL.
+func Upload(ctx context.Context, c PutObjectAPI, o Opts) (string, error) {
+	f, err := os.Open(o.FilePath)
+	if err != nil {
+		return "", fmt.Errorf("open %s: %w", o.FilePath, err)
+	}
+	defer f.Close()
+
+	if _, err := c.PutObject(ctx, &s3.PutObjectInput{
+		Bucket: aws.String(o.Bucket),
+		Key:    aws.String(o.Key),
+		Body:   f,
+	}); err != nil {
+		return "", fmt.Errorf("s3 put: %w", err)
+	}
+	return fmt.Sprintf("s3://%s/%s", o.Bucket, o.Key), nil
+}
+
+// WriteFileForTest is exposed for use from this package's tests.
+func WriteFileForTest(path string, b []byte) error {
+	return os.WriteFile(path, b, 0o600)
+}
+
+// NewClient builds an *s3.Client honouring an optional custom endpoint
+// for S3-compatible storage.
+func NewClient(ctx context.Context, region, endpointURL string) (*s3.Client, error) {
+	cfg, err := awsconfig.LoadDefaultConfig(ctx, awsconfig.WithRegion(region))
+	if err != nil {
+		return nil, fmt.Errorf("aws config: %w", err)
+	}
+	opts := []func(*s3.Options){}
+	if endpointURL != "" {
+		opts = append(opts, func(o *s3.Options) {
+			o.BaseEndpoint = aws.String(endpointURL)
+			o.UsePathStyle = true
+		})
+	}
+	return s3.NewFromConfig(cfg, opts...), nil
+}

internal/upload/upload_test.go

@@ -0,0 +1,88 @@
+package upload_test
+
+import (
+	"context"
+	"strings"
+	"testing"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+	"github.com/leonmika/wails-release/internal/upload"
+)
+
+func TestRenderKey(t *testing.T) {
+	cases := []struct {
+		template string
+		version  string
+		filename string
+		want     string
+	}{
+		{"releases/{version}/{filename}", "1.2.3", "App.app.zip", "releases/1.2.3/App.app.zip"},
+		{"{filename}", "1.0.0", "App.app.zip", "App.app.zip"},
+		{"app/{version}-{filename}", "1.2.3", "App.app.zip", "app/1.2.3-App.app.zip"},
+	}
+	for _, c := range cases {
+		got := upload.RenderKey(c.template, c.version, c.filename)
+		if got != c.want {
+			t.Fatalf("template %q: got %q want %q", c.template, got, c.want)
+		}
+	}
+}
+
+type fakePut struct {
+	calls []*s3.PutObjectInput
+}
+
+func (f *fakePut) PutObject(ctx context.Context, in *s3.PutObjectInput, _ ...func(*s3.Options)) (*s3.PutObjectOutput, error) {
+	f.calls = append(f.calls, in)
+	return &s3.PutObjectOutput{}, nil
+}
+
+func TestUpload_CallsPutObjectWithCorrectInputs(t *testing.T) {
+	tmp := writeTempFile(t, "hello")
+	c := &fakePut{}
+
+	url, err := upload.Upload(context.Background(), c, upload.Opts{
+		Bucket:   "my-bucket",
+		Key:      "releases/1.2.3/App.app.zip",
+		FilePath: tmp,
+	})
+	if err != nil {
+		t.Fatalf("unexpected: %v", err)
+	}
+	if url != "s3://my-bucket/releases/1.2.3/App.app.zip" {
+		t.Fatalf("url got %q", url)
+	}
+	if len(c.calls) != 1 {
+		t.Fatalf("expected 1 call, got %d", len(c.calls))
+	}
+	if aws.ToString(c.calls[0].Bucket) != "my-bucket" || aws.ToString(c.calls[0].Key) != "releases/1.2.3/App.app.zip" {
+		t.Fatalf("bucket/key wrong: %+v", c.calls[0])
+	}
+}
+
+func TestUpload_FailsWhenFileMissing(t *testing.T) {
+	_, err := upload.Upload(context.Background(), &fakePut{}, upload.Opts{
+		Bucket:   "b",
+		Key:      "k",
+		FilePath: "/does/not/exist",
+	})
+	if err == nil || !strings.Contains(err.Error(), "open") {
+		t.Fatalf("expected open error, got %v", err)
+	}
+}
+
+// writeTempFile creates a small temp file and returns its path.
+func writeTempFile(t *testing.T, contents string) string {
+	t.Helper()
+	dir := t.TempDir()
+	path := dir + "/blob"
+	if err := writeAll(path, contents); err != nil {
+		t.Fatal(err)
+	}
+	return path
+}
+
+func writeAll(path, s string) error {
+	return upload.WriteFileForTest(path, []byte(s))
+}